{	Problem: http://codeforces.ru/problemset/problem/68/B
 	Verdict: Accepted
}
uses sysutils;
var i,n,k,a,b:longint; l,r,x,up,dn:double; ar:array[1..10010] of longint; f:boolean;
procedure count_up(x:double; var na:longint; var s:double);
var i:longint;
begin
na:=0;
s:=0;
for i:=1 to n do
  if ar[i]>x then begin
    inc(na);
    s:=s+ar[i];
  end;
end;
procedure count_dn(x:double; var nb:longint; var s:double);
var i:longint;
begin
nb:=0;
s:=0;
for i:=1 to n do
  if ar[i]<=x then begin
    inc(nb);
    s:=s+ar[i];
  end;
end;
begin
read(n,k);
for i:=1 to n do read(ar[i]);
l:=0;
r:=10e9;
x:=0;
for i:=1 to 100 do begin
  x:=(l+r)/2;
  count_up(x,a,up);
  count_dn(x,b,dn);
  if (Up-A*X)*(100-K)/100.0>X*B-Dn then l:=x else r:=x;
end;
write(x:0:10);
end.